Rowan, you might be able to find some of the elevations you're after on www.cycle2max.com.
Go to the Hill climbs page>>Climbs in your area>> Australia>>Tasmania

You may even be able to add some of your own. They also have a very cool feature called ridemaker where you can plan a route through the Adelaide Hills and it will give you distances, ascent, starting and finishing altitudes and sometimes the state of the tarmac. It finishes with a ride profile so you can see where you may need to save a few bikkies.
Of course, this is only useful if you can ride the Adelaide Hills, but as I live in this region I find it very useful.